This invention relates to printing devices and is particularly directed to printing devices for use with computers and the like which printing devices are capable of performing multiple tasks.
It is common practice today, in many businesses, to maintain inventory, purchase order and billing information on a computer and to use a printer, controlled by the computer, to prepare invoices and address labels. Since the customer's name and address usually appear on the invoice, as well as the address label, it would be convenient to print both of these items substantially simultaneously. However, the invoice forms must contain considerable additional information and, hence, must be much larger than the address labels and the invoice forms must be fed to the printer with a much different advance pattern than the address labels.
It is possible to obtain combination forms which include both the invoice form and the address label, but these combination forms are quite expensive. Thus, it has been necessary, heretofore, to run the invoice forms and the address labels separately which requires additional time and manpower. For small businesses, especially the need to minimize costs is a matter of survival and any device which will facilitate this is greatly needed. In attempting to meet this need, there have been previous proposals for dual-delivery apparatus which would feed both types of forms to the printer. However, none of the prior art devices have been entirely satisfactory. A search in the U.S. Patent Office located the following:
______________________________________ U.S. Pat. No. Inventor Issued ______________________________________ 2,107,398 J. A. B. Smith Feb. 8, 1938 2,213,552 W. P. Scharr Sept. 3, 1940 2,348,059 G. F. Daly May 2, 1944 2,555,732 J. E. Dayger et al June 5, 1951 2,862,708 P. M. Allen Dec. 2, 1958 3,176,819 E. M. Bloom, Jr. et al April 6, 1965 4,027,765 L. L. Crump et al June 7, 1977 4,074,797 E. R. Lewis et al Feb. 21, 1978 4,229,113 T. H. Anderson et al Oct. 21, 1980 4,348,125 T. Fujiwara et al Sept. 7, 1982 4,382,704 W. Henrischk May 10, 1983 4,403,878 H. Hosogaya Sept. 13, 1983 4,439,051 R. L. Lawter Mar. 27, 1984 ______________________________________
The patent to Scharr teaches the use of a platen which is divided into two sections which may be driven either separately or simultaneously to permit feeding either one wide document or two smaller width documents which may be advanced together or independently. However, this adds considerable cost and complexity to the system. Furthermore, the need for Scharr to accommodate wide forms precludes the use of drive sprockets on the adjacent edges of the two platen sections. This tends to cause uneven advancement of the small forms driven by the two platen sections and is likely to cause jamming of the machine and tearing or crumpling of the forms.
The patent to Hosogaya disclses a printer feeding mechanism for feeding two separate forms but provides that the two may be advanced either in unison or at various rates. Again, this introduces considerable cost and complexity to the system.
The patent to Allen teaches apparatus for feeding two strips of forms to a printing machine in which both form strips are advanced simultaneously during one portion of the printing operation, and are advanced independently during other portions of the printing operation. In order to accomplish this, it is necessary for Allen to include a transmission for controlling the drive mechanism and this greatly increases the cost and complexity of the system.
The patents to Anderson and Hendrischk are directed to ancillary devices, such as roll end detectors, while the patents to Bloom, Crump, Lewis and Lawter relate to devices which are clearly much more complicated and expensive than the present invention.
In the examination of the parent application, the following references were cited:
______________________________________ Pat. No. Inventor Issued ______________________________________ 2,047,233 J. Q. Sherman July 14, 1936 2,326,291 E. S. Doldge et al Aug. 10, 1943 3,850,355 J. Downie et al Nov. 26, 1974 4,417,825 J. E. Cushman et al Nov. 29, 1983 DE 30 14 609 41 Mannesmann AG April 14, 1980 ______________________________________
The Sherman reference discloses a conventional typewriter mechanism having a multi-sectional platen. The platen is fixedly held but rotatable within a recipricatory platen carriage, requiring a traveling carrier for the stationary supply. However, there is no means to selectively couple one or the other of the platen sections by an electrically operated clutch system. Further, the only manual adjustable stop is by means of the margin set and margin release functions of the conventional typewriter, which can only be entered through the keyboard and not controlled by a computer.
The Downie, et al reference is directed to a multisectional form feed device, which can function as a split platen. The system makes use of a plurality of pressure roll assemblies, as opposed to multiple pin feed assemblies, driven by a stepper motor. The stepper motor is provided with two mechanicallv operated unidirectional clutch assemblies. Thus, selection of which form is to be advanced can be accomplished electrically by operating the motor in a counter-clockwise direction the required number of rotational steps, or manually by manual rotation of its cam shaft. However, to electrically advance the cam shaft to select which forms to be spaced by its drive roller, the motor must reverse direction subsequent to driving the cam shaft in order to advance the paper Having rotated counter-clockwise a specified number of steps in order to position the cam shaft, the motor must then subsequently rotate clockwise in order to drive the roller to advance the selected form a predetermined number of steps. Because a stepper motor is utilized, the position of the cam shaft must be encoded to provide automatic selection of the proper cam shaft position, and since the motor must rotate a specific number of steps from its previous position a counter or counters must be utilized in the circuitry to monitor motor position.
The Downie et al reference fails to disclose a drive system for a split platen having a clutch to selectively connect a desired one of the two platens responsive to (1) a control signal from a computer and (2) a manual displacement handle member of the clutch assembly.
The other references cited were directed to typewriter-type mechanisms for moving paper.